Calorimeter.



J; R. BIBBINS.,

GA'LOMMBTER. APPLIUATION IILED AUG. 7, 1906.

Patented Mar. 11, 1913.

INVIATO/f. /MAM o ATTORNEY.

vBINS, a citizen of the United 4UNITED STATES PATENT ori-uen L JAMES n. BIBBINS, lor PITTSBURGH, PENNSYLVANIA, Ass1GNoR,-BY MESNE ASSIGN- ENTS, TO THE COLONIAL TRUST COMPANY, VANIA, A. CORPORATION OF PENNSYLVANIA TRUSTEE, F PITTSBURGH, PENNSYL- CALORIME'TER.

Specification of Letters Patent.

Application flied August 7, 190e. serial No. 329,584. l

. duction of an apparatus which may be utilized With various types of calorimeters andV which will indicate or record the 'number of thermal units per. cubic -foot of the i gas tested and thereby eliminate the' necessity' of tedious observations and computations.

This Vand other objectsy I obtain with anapparatus embodying the featuresherein described and illustrated.

In the drawings accompanying this alpplication and forming a part thereof, Figure 1 illustrates, somewhatdiagrammatically, an apparatus embodying my invention, a portion of the apparatus being shown in elevation and a portion in plan for con'- venience of illustration; view of a detail of my 30 and E1g.2 is a side invention.

While I have illustrated my invention in connection 'with a differential and pressure type of calorimeter, I desire it to be specically understood that I do not limit its application toany specific type of calorimeter,

as it will be apparent to A those skilled in the art that it is equally applicable toA calorimeters employing the expansive force of a heat-responsive agent s a means of indicating the' .calorific Va ue of the gas or other fuel material tested.

. Referring to Figs. land 2: A calorimeter 3, which has the customary form of combus; tion chamber, is provided I With aW-ater inlet port 4 and an outlet port 5. As` is cus`l tomary the water entering the calorimeter is conductedinto close proximity 'with the Y combustion chamber so that 1t mayabsorb the heat'developed by the combustion of the material orrfueltested. A receptacle or receiver @interposed between the1 source of water supply and the `port 4,115 yarranged to' -receive a thermometer 7. A receptacle -8 receives the Water discharged fromthe RoivLAND BIB` States, and av -below the surfaceof the them. f The thermometers 7 and 9 are air or port 5 and4 is tel' 9.

| The thermometers 7 and. 9 each consists provided with -a thermome- Patentea Mar; 1 1, 1913.

of a bulb 10 and an'integrally-formed tube I' 11. The tube 11- of the thermometer@v communicates .through .aport' 12 with a receptacle 13.and' the tube of the thermometer; 9

communicates through a por-t 15 with a recept-acle 16.` The 'receptacle '13 .is partially.4

filled with al high electrical resistance' liquid and the receptacle 16 is partially filled with a low resistance liquid, such as mercury. 12 and 15 are 'located above the surface of the liquid contained in'their refspective receptacles.4 y

U-shaped capillary tube 14 connectsthe' receptacles 13 and 16 and is so arranged that' it communicates with each receptacle liquid contained'by gas thermometers and with the `recept-acles 13 and 16 and the tube 14 form a closed sys- 'The bulbs 10 of the' thermometersareof .such size, relative to the volume of the interior of the tubes 11, that the accuracy of the thermometers in registeringthe variations of temperature of the Water-.is not materially affected by theL variations in volume of the fluid inthe tubes.

tern.' all the joints being hermetically sealed.

vvThe tube 14 is partially filled with high resistance liquid from'the receptacle 13-an'd 'the' remainder with mercury from the receptacle 16. Variationsin the temperature of the water entering the calo'imeter through the port 4 cause variations in density of the air in the bulb 10 of the t-her mometer andconsequently variations of air pressure above the liquid in .the receptacle'13. Variations of temperature in` theI Water discharged fromthe calorimeter like# Wise cause variations of pressure above. As the` the mercury in theV receptacle 16. temperature of the Water discharged vfrom the calorimeter increases above vthat. of the Water enteriig the calorimeter, the air lpressure-in fthe receptacle 16 predominates over the pressure vinthe receptacle 13 and mercury is forbed into the tube 14, the-high resistance Huid which `is displaced vbeing forced back intothereceptacle 13. As the temperature, fthe 'Water discharged from the calorimeterdecreases, the length of the I into the tube 14 to take the place of the .receding mercury.v Withsuch an arrangement the variations iii temperature of the `Water entering and leaving the calorimeter cause the point of contact of mercury and high resistance liquid in the tube 14 to fluetuate.. The tube 14 is graduated int-o segments of equal length and thehigh resistance liquid and the mercury vare so arranged that the point of contact of the mercury and the' high resistance fluid in th'e tube will stand opposite the Zero graduation when the pressure in each of the receptacles 13 and 16 is equal. l

A primary or other cell 17 of constant discharge characteristics, or some other source lof 4constant electroiiiotive force i-s connected into an electric circuit which includes an electric meter or current'indicating device 21, the mercury receptacle' 1G, the tube 14 and the high resistance liquid receptacle 13.' The battery 17 is connected to a terminal of the meter or indicating device 21 by a Wire 18. The other terminal of t-lie indicating device is connected with the mercury iii the receptacle 1G by a vvire 19 and the high resistance liquid in the receptacle 13 isv connected to thebattery 17 by a wire 20.

The operation of the recording device isA as follows: Variations in temperature of the i Water entering and leaving the calorimeter cause variations in pressure in the receptacle 16 and, as'has been described, variations in the position of the pointof contact bet-Ween the mercury and the high resistance liquid in the tube 14 in accordance With the pressure in their respective receptacles. Since the point of contact occupies the Zero position when the pressures in vthe receptacles are equal, any increase iii the-length of the mercury column will indicate an increase o'f pressure in the receptacle 1G above that in the receptacle lf3 -and since the pressures are directly proportional to the temperatures of the air in the ybulbs 10v of the thermometers, the mercury column will iiicrease and decrease in length lin accordance with the variations in temperature of the Water Aleaving thev calorimeter. Q'Ih'e wires connecting the receptacles 1G and. 1Std the battery 17 are of such cross-sectional area' that their resistance is negligible. The relative resistance of the mercury is also negligible and the arrangement is 4such that the resistance introduced into the circuit is 'directly proportional to the length of the column of high resistance liquid in the tube 14. The contact between the. niercurv and V the high resistance liquid acts as a frictionless rheosta't arm and the amount of resist-- ance inthe circuit' is directly proportional to the didereuce of temperature between the ivater entering and leaving the calorimeter. Thedilierential effects of gravity do hot have to be reckoned with lsince the levels of y the liquid in the receptacles '13 and 16 are practically constant, owing to their large volume as compared with that of the tube 14.' The raduations of the tube 14 may indicate di or B. T. Us.

The electric meter 21, which indicates the amount of current flowing through the cirerences of pressure, teinpeiaturer cuit, is graduated in British thermal units per cubic foot of gas, as the resistance' in the circuit variesin direct proportion tothe differences of temperature as recorded by the thermometers.

Vith the differential arrangement of the thermometers, it. is not necessary to measure the absolute temperature of the Water entering and leaving the calorimeter, as the circuit is a closed or balanced circuit. The instrument, therefore, is only sensitive to differences of temperature and the labor -and inaccuracies involved in reading teniperatures are avoided.

In accordance With the provisions of the patent statutes, I have described the principle of operation ot' my invention, together `With the apparatus vvhich I now consider to represent the best lembodiment thereof, but I desire to have it understood that `the apparatus yshown is only illustrative and that the invention can be carried out by other means. 4 I

What I claim is:

1. In combination with a calorimeter, an electric circuit includinga source of constant potential, and electrical devices included in said circuitfor indicating, in ther-v mal units, the amount otheat developed in` ico cuit and provided with a high resistance liquid receptacle at one end and a low resistance liquid receptacle at the-other end, and means, responsive to the temperature variations in said calorimeter, for .varying the amount of resistance included in said circuit by varying the length 'of the column of high resistance liquid 'in said tube.

2. In combination ivith'a calorinieteigan electrical device forindicating ther amount of heat developed in the calorimeter, an'electric circuit in which said device is located, `a

iis

-var'iable electrical resistance in said circuit and comprising -a' tube provided with a high resistance liquid receptacle at one end' and a low vresistance liquid receptacle at the other end, and means, responsiveto. temperature variations vin said calorimeter, for varying the amount of resist-ance included in said circuit, by varying the length of` lthehigh resistance liquid column in said tube. j

3i In en indicating device'fo'r caloriine# fiers, anrlectric circuit including a -souice of constant potential, a meter and a 'variable resitenbe device omprisi'ng atube provided Wit one ,end' andl slow resist tacleatthe other end, sensitive t the amunt` of heat "developed m si calorimeters Iand Aa, rra, 11gecl 4to 'vary the amount of resist-ance mclud'ed'- 1n said r a. high resistatnce liquid receptale at.

ance liquid recepfluid thermometers circuity by `viaryig the `relative lengths of .the Columns of liquid in' said-tube.' v IIn 'ttimoinywhereof', I have hereunto subscribed my name' this 4th daylf -Ai'lgilsc" 1906. l

'JAMES R, 'BIBisi-Ns.

Witnesses: l V CHARLES W. MCGHEE', 

